A number of men were engaged in raising and lining up the track in the approach to the large open pit when a landslide of a great quantity of ore from the north side occurred so suddenly that the men had no time to escape, and 14 were caught and killed. At the place where the accident occurred the pit was 358 feet wide from crest to crest of the ore body and 51 feet wide at the bottom; its depth was 205 feet.

The bank thus had some slope, but the dip of the ore was toward the south, providing greater opportunity for sliding. It is assumed that the bank had been loosened by alternate thawing and freezing. It appears that the men had no idea that the place was dangerous, because it was used as a place of refuge when blasting was being done.